Synthesis and structural diversity of d¹⁰ metal coordination polymers constructed from new semi-rigid bis(3-methyl-1H-pyrazole-4-carboxylic acid)alkane ligands

Abstract

Three isomeric ligands, and four d10 metal CPs were synthesized, varying from 1D to 2D, together with achirality to chirality variation.

Synthesis and Structural Diversity of Main Group Metal Coordination Complexes Constructed from V‐Shape Bis(3‐methyl‐1H‐pyrazole‐4‐carboxylic acid)alkane Ligands

“…The bis(3‐methyl‐1H‐pyrazole‐4‐carboxylic acid)methane ligands exhibited four different coordination modes in the four reported Zn(II)/Cd(II) complexes, acted as μ 2 − and μ 3 −connectors . While in the tittle compounds 1–5 , another five coordination modes are firstly occurred, which acted as monodentate ligand, μ 2 −, μ 3 − and μ 5 −connectors, respectively.…”

“…(L 1 ) 2− /(L 2 ) 2− anions in 1 – 4 adopted trans ‐configuration, while in 5 , the (L 3 ) 2− anion adopted cis ‐configuration. The (L 1 ) 2− /(L 2 ) 2− anions in reported Zn(II) and Cd(II) CPs, [Zn(L 1 )(H 2 O) 2 ] n ⋅nH 2 O, Cd(L 1 )(H 2 O)] n ⋅nH 2 O and [Cd(L 2 )(H 2 O)] n ⋅2nH 2 O⋅nEtOH, also adopted cis ‐configuration, but they coordinated to metal ions not noly by O donors from the carboxylate groups but also by N atoms from pyrazole rings . Which may be due to the main group metal ions have relatively larger radius and is strongly oxophilic, compared with transition metal ions.…”

“…In the past decades, pyrazolecarboxylic acid as a rigid and multifunctional bridge has been extensively used to construct complexes . In the resulting complexes, they coordinated to metal ions not only in a N,O‐chelating fashion but also in bridging mode acting as μ 2 ‐, μ 3 ‐, μ 4 ‐, μ 5 ‐ and so on connectors.…”

“…In the resulting complexes, they coordinated to metal ions not only in a N,O‐chelating fashion but also in bridging mode acting as μ 2 ‐, μ 3 ‐, μ 4 ‐, μ 5 ‐ and so on connectors. Hence, our group is actively involved in the construction and systematic investigation of pyrazolecarboxylic acids CPs and their applications . In addition, we have paid more attention to functionalize 3‐methyl‐1H‐pyrazole‐4‐carboxylic acid, and synthesized three isomeric bis(3‐methyl‐1H‐pyrazole‐4‐carboxylic acid)methane ligands, namely, (1,1'‐methylenebis(5‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 1 ), 1, 2'‐methylenebis(3‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 2 ) and 1,1'‐methylenebis(3‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 3 )), which have been successfully used to construct CPs with d 10 metal ions .…”

“…Hence, our group is actively involved in the construction and systematic investigation of pyrazolecarboxylic acids CPs and their applications . In addition, we have paid more attention to functionalize 3‐methyl‐1H‐pyrazole‐4‐carboxylic acid, and synthesized three isomeric bis(3‐methyl‐1H‐pyrazole‐4‐carboxylic acid)methane ligands, namely, (1,1'‐methylenebis(5‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 1 ), 1, 2'‐methylenebis(3‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 2 ) and 1,1'‐methylenebis(3‐methyl‐pyrazole‐4‐carboxylic acid (H 2 L 3 )), which have been successfully used to construct CPs with d 10 metal ions . The structures of the four reported Zn(II) and Cd(II) CPs, vary from 1D chain to 2D layer, together with from achirality to chirality, the (L 1 ) 2– /(L 2 ) 2– anions in which show two conformations ( cis and trans ), along with four coordination modes by the N and O donor atoms.…”